Update regarding the society of American Gastrointestinal and Endoscopic Surgeons (SAGES) grant distribution and impact on recipient's academic career.

BACKGROUND: Small seed grants strongly impact academic careers, result in future funding, and lead to increased involvement in surgical societies. We hypothesize that, in accordance with the SAGES Research and Career Development committee mission, there has been a shift in grant support from senior faculty to residents and junior faculty. We hypothesize that these junior physician-researchers are subsequently remaining involved with SAGES and advancing within their academic institutions. METHODS: All current and previous SAGES grant recipients were surveyed through Survey Monkey™. Questions included current academic status and status at time of grant, ensuing funding, publication and presentation of grant, and impact on career. Results were verified through a Medline query. SAGES database was examined for involvement within the society. Respondent data were compared to 2009 data. RESULTS: One hundred and ninety four grants were awarded to 167 recipients. Of those, 75 investigators responded for a response rate 44.9%. 32% were trainees, 43% assistant professors, 16% associate professors, 3% full professors, 3% professors with tenure, and 3% in private practice. This is a shift from 2009 data with a considerable increase in funding of trainees by 19% and assistant professors by 10% and a decrease in funding of associate professors by 5% and professors by 10%. 41% of responders who were awarded the grant as assistant or associate professors had advanced to full professor and 99% were currently in academic medicine. Eighty-two percent indicated that they had completed their project and 93% believed that the award helped their career. All responders remained active in SAGES. CONCLUSION: SAGES has chosen to reallocate an increased percentage of grant money to more junior faculty members and residents. It appears that these grants may play a role in keeping recipients interested in the academic surgical realm and involved in the society while simultaneously helping them advance in faculty rank.

SAGES research agenda in gastrointestinal and endoscopic surgery: updated results of a Delphi study.

BACKGROUND: Research in gastrointestinal and endoscopic surgery has witnessed unprecedented growth since the introduction of minimally invasive techniques in surgery. Coordination and focus of research efforts could further advance this rapidly expanding field. The objective of this study was to update the SAGES research agenda for gastrointestinal and endoscopic surgery. METHODS: A modified Delphi methodology was used to create the research agenda. Using an iterative, anonymous web-based survey, the general membership and leadership of SAGES were asked for input over three rounds. Initially submitted research questions were reviewed and consolidated by an expert panel and redistributed to the membership for priority ranking using a 5-point Likert scale of importance. The top 40 research questions of this round were then redistributed to and re-rated by members, and a final ranking was established. Comparisons were made between membership and leadership responses. RESULTS: 283 initially submitted research questions were condensed into 89 distinct questions, which were rated by 388 respondents to determine the top 40 questions. 460 respondents established the final ranking of these 40 most important research questions. Topics represented included training and technique, gastrointestinal, hernia, GERD, bariatric surgery, and endoscopy. The top question was, "How do we best train, assess, and maintain proficiency of surgeons and surgical trainees in flexible endoscopy, laparoscopy, and open surgery?" 28% of responders were leadership and the rest general members with the majority of ratings (73%) being similar between the groups. While SAGES leadership rated the majority of questions (89%) lower, they rated nonclinical questions higher compared with general membership. CONCLUSIONS: An updated research agenda for gastrointestinal and endoscopic surgery was developed using a systematic methodology. This agenda may assist investigators and funding organizations to concentrate their efforts in the highest research priority areas and editors and reviewers in assessing the merit and relevance of scientific work.

Consumer-based technology for distribution of surgical videos for objective evaluation.

BACKGROUND: The Global Operative Assessment of Laparoscopic Skill (GOALS) is one validated metric utilized to grade laparoscopic skills and has been utilized to score recorded operative videos. To facilitate easier viewing of these recorded videos, we are developing novel techniques to enable surgeons to view these videos. The objective of this study is to determine the feasibility of utilizing widespread current consumer-based technology to assist in distributing appropriate videos for objective evaluation. METHODS: Videos from residents were recorded via a direct connection from the camera processor via an S-video output via a cable into a hub to connect to a standard laptop computer via a universal serial bus (USB) port. A standard consumer-based video editing program was utilized to capture the video and record in appropriate format. We utilized mp4 format, and depending on the size of the file, the videos were scaled down (compressed), their format changed (using a standard video editing program), or sliced into multiple videos. Standard available consumer-based programs were utilized to convert the video into a more appropriate format for handheld personal digital assistants. In addition, the videos were uploaded to a social networking website and video sharing websites. RESULTS: Recorded cases of laparoscopic cholecystectomy in a porcine model were utilized. Compression was required for all formats. All formats were accessed from home computers, work computers, and iPhones without difficulty. Qualitative analyses by four surgeons demonstrated appropriate quality to grade for these formats. CONCLUSIONS: Our preliminary results show promise that, utilizing consumer-based technology, videos can be easily distributed to surgeons to grade via GOALS via various methods. Easy accessibility may help make evaluation of resident videos less complicated and cumbersome.

Decrease in sweet taste in rats after gastric bypass surgery.

BACKGROUND: The literature contains evidence that Roux-en-Y gastric bypass (RYGB) surgery has an effect in humans on taste and preference for carbohydrate-rich foods. This study tested the hypothesis that RYGB affects sweet taste behavior using a rat model. METHODS: Male Sprague-Dawley rats underwent either RYGB or sham surgery. Then 4 weeks after surgery, the rats were given taste-salient, brief-access lick tests with a series of sucrose concentrations. RESULTS: The RYGB rats, but not the sham rats, lost weight over the 5-week postoperative period. The RYGB rats showed a significant decrease in mean licks for the highest concentration of sucrose (0.25-1.0 mol/l) but not for the low concentrations of sucrose or water. CONCLUSIONS: The findings showed that RYGB surgery affected sweet taste behavior in rats, with postsurgical rats having lower sensitivity or avidity for sucrose than sham-treated control rats. This finding is similar to human reports that sweet taste and preferences for high-caloric foods are altered after bypass surgery.

Unsupervised procedures by surgical trainees: a windfall for private insurance at the expense of graduate medical education.

BACKGROUND: Surgical faculty cannot always be present while trainees perform minor procedures. Fees are not obtained for these unsupervised services because Medicare rules do not allow residents and fellows to bill. Medicare already supplements hospitals via medical education funds and thus reimbursement for trainee services would constitute double billing. Private insurance companies, however, do not supplement trainees' salaries and thus benefit when they are not charged for these procedures. The objective is to determine whether significant revenue is lost to private insurers for unsupervised procedures performed by surgical trainees. METHODS: We retrospectively evaluated a prospective database of procedures performed by residents and fellows from March 1998 through 2007. All procedures were entered by the trainees into a computerized electronic note system. Unsupervised procedures were not billed to insurance carriers. RESULTS: During the study period, 14,497 minor procedures were performed without attending supervision, of which 13,343 had valid current procedural terminology codes. Total charges for these procedures would have been $10,096,931. For patients with private insurance companies (PICs), $6,876,000 could have been billed. Using our historic collection ratios, $2,269,083 in revenue was lost, or $232,726 annually. CONCLUSIONS: Trainees perform a significant number of unsupervised procedures on patients with private insurance without charge. This pro bono service represents a significant amount of lost income for teaching institutions. Private insurance companies benefit financially from Medicare billing regulations without contributing to education. Billing for these services might help offset the costs of graduate medical education.

Technical skills rotation for general surgery residents.

BACKGROUND: Technical skills are an important part of any general surgery residency curriculum. With the demands of limited work weeks, it is imperative that educators create novel methods of teaching technical skills to their residents. Our program utilizes a dedicated month to help accomplish this. This study hypothesized that general surgery residents would report a positive effect of a dedicated technical skills rotation. METHODS: Residents who had undergone a 1 mo rotation in technical skills during their first year were asked to fill out a survey concerning their experience. During the 1-mo rotation, the residents had almost no clinical responsibilities. Teaching of technical skills was performed with various activities, including video content (VC), virtual reality simulators (VR), open foam procedures (OF), laparoscopic box trainers (BT), surgical equipment in-service (SE), and animate sessions (AS). Responses were given on a Likert scale (1-10) with higher numbers being more positive responses. RESULTS: There were seven residents in this study. The residents gave a very positive response to the overall rotation (9.4) and exposure to laparoscopic procedures (9.6). The other responses were enthusiastic as well: exposure to open procedures (8.9) and preparation for operative room (9.4). After their rotation, the residents were comfortable performing a laparoscopic cholecystectomy (9.2), a hand-sewn anastomosis (8.7), and a stapled anastomosis (9.4). The residents found theses activities helpful in increasing order: VC (7.8), VR (8.0), BT (9.0), ES (9.7), OF (9.8), and AS (9.8). CONCLUSIONS: A 1-mo dedicated technical skills rotations was perceived to be extremely positive by the residents. The residents felt very comfortable performing a laparoscopic cholecystectomy, a hand-sewn anastomosis, and a stapled anastomosis. With the 80-h work week, alternatives to learning technical skills in the operating room are essential. Further studies need to be performed to determine if this rotation aids in accomplishing this goal.

Internal Hernias and Nonclosure of Mesenteric Defects During Laparoscopic Roux-en-Y Gastric Bypass.

BACKGROUND: Internal hernias have been described after laparoscopic Roux-en-Y gastric bypass (LRYGB) as a major problem. Thus, many routinely close defects during LRYGB. In our technique, we do not close any defects. We hypothesize that not closing the defects would not cause a significant internal hernia rate diagnosed during reoperations. METHODS: Patients who were reoperated after LRYGB were included in this study. Only patients who had a laparoscopic or open exploration focused on inspecting for internal hernias are reported here. The LRYGB technique that was utilized included an antecolic, antegastric gastrojejunostomy, minimal division of the small bowel mesentery, a long jejunojejunostomy performed with three staple lines, adequate division of the omentum, and placement of the jejunojejunostomy above the colon in the left upper quadrant. RESULTS: There were a total of 387 patients who had LRYGB from 2002 to 2007 utilizing this particular technique. Fifty-four patients had a reoperation at an average of 24 (Range: 1-60) months postoperatively. The procedures were abdominoplasty, cholecystectomy, diagnostic laparoscopy, and lysis of adhesions. While two patients had a defect present, no patient had an internal hernia despite aggressive attempts to diagnose one. CONCLUSIONS: Internals hernias are not common after our particular method of LRYGB. Before adopting and advocating routine closure, surgeons should consider the surgical technique and the true associated incidence of internal hernias. We do not recommend routine closure of these defects with our technique.

Omental reinforcement for intraoperative leak repairs during laparoscopic Roux-en-Y gastric bypass.

Leaks from the gastrojejunostomy after laparoscopic Roux-en-Y gastric bypass (LRYGB) have the potential for significant morbidity and mortality. When intraoperative leaks are discovered, we choose to perform omental reinforcement around the gastrojejunostomy and pouch after suture repair of the leaks. This study examined the hypothesis that omental reinforcement would be useful after intraoperative leaks during LRYGB. Omental reinforcement was performed on gastrojejunostomies, in which leaks were seen, created using a circular stapler during LRYGB. Data were reviewed retrospectively on these patients. There were a total of 387 patients with 32 (8.26%) patients who had a staple line dehiscence or evidence of gastric pouch or gastrojejunostomy leak intraoperatively. Leaks/dehiscences were repaired with sutures and then reinforced with omentum. None of these patient developed anastomotic leak postoperatively. Of the other 365 patients, there were four (1.1%) leaks from the gastrojejunostomy and/or gastric pouch. Omental reinforcement may be useful in decreasing the incidence of postoperative leaks when an intraoperative leak is encountered during LRYGB. However, omental reinforcement does not completely prevent a postoperative leak. Consideration of reinforcement with omentum may be given for patients in whom an intraoperative leak is noted.

Intraoperative endoscopy and leaks after laparoscopic Roux-en-Y gastric bypass.

Postoperative leaks after laparoscopic Roux-en-Y gastric bypass (LRYGB) are a source of morbidity and mortality. Any intervention that would decrease leak rates after LRYGB would be useful. This investigation tested the hypothesis that postoperative leak rates are lower after LRYGB with the routine use of intraoperative endoscopy (EN). Consecutive patients who underwent LRYGB were included. Intraoperative leak testing with air and methylene blue through an orogastric tube (OG) was used in the first 200 patients. Intraoperative endoscopy was used after the first 200 patients. There were 400 patients in this study. Preoperative demographics did not differ between groups. The intraoperative leak rate of the EN group was double the OG group (8 vs 4%; P = not significant), although the difference was not statistically significant. The OG group had a postoperative leak rate of 4 per cent with a mortality rate of 1 per cent. The EN group had a postoperative leak rate of 0.5 per cent with a mortality rate of 0 per cent. The difference in leak rates was statistically significant (P < 0.04). Despite the issues of learning curve, EN demonstrates more intraoperative leaks than OG, indicating EN may be a more sensitive test than OG. Routine use of EN is associated with less postoperative leaks after LRYGB.

Management of recurrent inguinal hernias after total extraperitoneal (TEP) herniorrhaphies.

INTRODUCTION: The laparoscopic repair offers clear advantages in recurrent inguinal hernias after open herniorrhaphy. Less clear is the role of laparoscopy for recurrences after previous laparoscopic inguinal herniorrhaphies. In this paper, we present our experience with both laparoscopic and open inguinal hernia repair of laparoscopic recurrences. METHODS: All patients who had undergone repair of recurrences after previous laparoscopic hernia repair from July 2004 to July 2007 were included in this study. Charts were reviewed for all these patients. RESULTS: Six patients were diagnosed with 7 recurrent inguinal hernias after laparoscopic repairs. All the initial laparoscopic repairs, except for one, were total preperitoneal (TEP) with the placement of lightweight polypropylene mesh. The average time from the initial repair to the diagnosis of recurrence was 20 months (range 3-84). Four of the 7 recurrences were treated with a laparoscopic approach. The other three recurrences were repaired in an open fashion as per the preoperative plan. In 2 of the laparoscopic cases, the peritoneal flap was not able to cover the mesh, so a tissue-separating mesh with fibrin sealant was utilized to cover the myopectineal orifice. No intra- or postoperative complications were recorded. There were no recurrences at an average follow-up of 14 months (range, 11-17). CONCLUSIONS: Laparoscopic repair can be offered to those patients with a recurrence after a previous laparoscopic repair. Further studies comparing laparoscopic repair versus open repair of recurrences after laparoscopic inguinal hernia repair will be helpful in defining the best approach when encountering these recurrences.

Laparoscopic revision of failed fundoplication and hiatal herniorraphy.

OBJECTIVE: The aim of this study was to evaluate the mechanisms of failure after laparoscopic fundoplication and the results of revision laparoscopic fundoplication. BACKGROUND: Laparoscopic Nissen fundoplication has become the most commonly performed antireflux procedure for the treatment of gastroesophageal reflux disease, with success rates from 90 to 95%. Persistent or new symptoms often warrant endoscopic and radiographic studies to find the cause of surgical failure. In experienced hands, reoperative antireflux surgery can be done laparoscopically. We performed a retrospective analysis of all laparoscopic revision of failed fundoplications done by the principle author and the respective fellow within the laparoscopic fellowship from 1992 to 2006. METHODS: A review was performed on patients who underwent laparoscopic revision of a failed primary laparoscopic fundoplication. RESULTS: Laparoscopic revision of failed fundoplication was performed on 68 patients between 1992 and 2006. The success rate of the laparoscopic redo Nissen fundoplication was 86%. Symptoms prior to the revision procedure included heartburn (69%), dysphagia (8.8%), or both (11.7%). Preoperative evaluation revealed esophagitis in 41%, hiatal hernia with esophagitis in 36%, hiatal hernia without esophagitis in 7.3%, stenosis in 11.74%, and dysmotility in 2.4%. The main laparoscopic revisions included fundoplication alone (41%) or fundoplication with hiatal hernia repair (50%). Four gastric perforations occurred; these were repaired primarily without further incident. An open conversion was performed in 1 patient. Length of stay was 2.5 +/- 1.0 days. Mean follow-up was 22 months (range, 6-42), during which failure of the redo procedure was noted in 9 patients (13.23%). CONCLUSION: Laparoscopic redo antireflux surgery, performed in a laparoscopic fellowship program, produces excellent results that approach the success rates of primary operations.

Stimulation of human omental adipose tissue lipolysis by growth hormone plus dexamethasone.

Growth hormone [GH] administration results in a reduction in adiposity of humans that is attributed to stimulation of lipolysis. We examined the effect of direct addition of human GH, in both the absence and presence of dexamethasone [Dex], as well as that of interferon beta on lipolysis by omental adipose tissue explants from obese women incubated for 48h in primary culture. There was a significant stimulation of lipolysis by GH in the presence of Dex but not by Dex or GH alone. There was also a significant further stimulation by GH in the presence of Dex of hormone-sensitive lipase, perilipin, lipoprotein lipase and beta1 adrenergic receptor mRNA. We conclude that the direct lipolytic effect of GH is accompanied by an increase in HSL mRNA in the presence of DEX, but GH also increased the mRNAs for other proteins that could explain all or part of its lipolytic action.

Natural orifice transluminal endoscopic gastric bypass performed in a cadaver.

Natural orifice transluminal surgery (NOTES) offers a new option for abdominal surgery. However, despite the initial interest and enthusiasm for its potential advantages, NOTES has some major drawbacks which include the purposeful injury to an organ that may not be otherwise injured or diseased. Roux-en-Y gastric bypass may be a procedure that is suited for NOTES because the stomach wall is breached during the normal course of the operation. We have experimented with a technique for a NOTES gastric bypass in the human. A transvaginal, transgastric gastric bypass (TVTG-GBP) was performed in a human cadaver.

Patients who are delayed from undergoing bariatric surgery do not have improved weight loss.

BACKGROUND: Many patients have a prolonged wait time between initial surgeon visit and actual surgery day. Whereas there are various reasons for this, few have examined if patient wait time for bariatric surgery has any affect on weight loss. This investigation studies the hypothesis that patients who wait longer for bariatric surgery do not have improved weight loss over those with shorter wait times. METHODS: All patients in a private academic practice who underwent laparoscopic gastric bypass over a 6-month period were included in this study. The time from initial office visit to actual surgery date was calculated to be wait time (WT). Reasons for short or long WT were not investigated. The relationship between WT and percentage excess body weight loss (%EBWL) was examined. In addition, patients whose WT was greater than 6 months (WT > 6) were compared to those less than 6 months (WT < 6). Pearson's correlation coefficients and two-tailed Mann-Whitney tests were used as appropriate. RESULTS: There were 104 patients with 99 patients who had a >1 year follow-up. WT did not correlate with %EBWL (r = 0.09, p = 0.37). There was no difference in %EBWL in the WT > 6 group versus the WT < 6 group (73 vs. 70%; p = NS). Patients who had <50% EBWL waited an average of 281 versus 254 days for those who have >50% EBWL (p = NS). CONCLUSIONS: Patients who wait longer before having bariatric surgery do not show improved weight loss. Weight loss success was not related to wait time. These results suggest that prolonged mandatory weight times are not an effective method for improving bariatric surgery weight loss outcomes. Mandatory delays for bariatric surgery should not be required, as they have no scientific merit.

Monitored anesthesia care with propofol versus surgeon-monitored sedation with benzodiazepines and narcotics for preoperative endoscopy in the morbidly obese.

BACKGROUND: Although still controversial, upper endoscopy is frequently performed before bariatric surgery. This study investigated the hypothesis that morbidly obese patients would prefer anesthesiologist-monitored sedation (AMS) compared to surgeon-monitored sedation (SMS) during preoperative endoscopy. METHODS: All patients who underwent endoscopy before their bariatric surgery were given a post-procedure survey regarding their experience with the preoperative endoscopy. The survey inquired about issues during and after the procedure. We compared patients who had AMS with IV propofol versus SMS IV narcotics and benzodiazepines. RESULTS: There were 100 patients (SMS=49 and AMS=51). Few patients complained of pain in the abdomen or throat during the procedure (AMS vs. SMS=2 vs. 8% and 2 vs. 10%, respectively; p=NS). More patients complained about throat pain after the procedure (AMS vs. SMS=37 vs. 45%; p=NS). More patients in the SMS group remembered the scope being placed in the mouth versus AMS (33 vs. 10%; p<0.02). More patients remembered gagging during the procedure in the SMS group versus the AMS group, but this did not reach statistical significance (24 vs. 10%; p=0.06). There was a trend that more patients in the AMS group felt they recovered in less than 1 h (53%) compared to the SMS group (37%; p=0.1). CONCLUSION: Patients who undergo upper endoscopy with either AMS or SMS seem to tolerate the procedure well. The preliminary benefits seen with AMS need to be further explored. AMS should be considered for patients undergoing preoperative upper endoscopy before bariatric surgery.

Effect of preoperative knowledge on weight loss after laparoscopic gastric bypass.

INTRODUCTION: Gastric bypass surgery has been demonstrated to be an effective treatment for morbid obesity. Unfortunately, not all patients have the same weight loss after surgery. It may be that the more informed patients will have more weight loss than less informed patients. No study has investigated the relationship between initial preoperative knowledge and weight loss after laparoscopic gastric bypass surgery. METHODS: All patients who underwent laparoscopic gastric bypass for a 6-month period were included in this study. Our preoperative education process includes a 21-question true/false test given at the appointment immediately before surgery. Patients repeat the test until all questions are answered correctly. We compared percentage of excess body weight loss (EBWL) between patients who correctly answered all the questions the first time (pass patients) and patients who did not correctly answer all the questions the first time (fail patients). RESULTS: There were 104 patients involved in this study; although complete data were only available on 98 patients. The average preoperative body mass index was 48 kg/m(2). Forty-eight percent of patients answered all the questions correctly the first time. Follow-up ranged from 1 to 2 years on all 98 patients. Pass patients had an average of 73% EBWL, whereas fail patients had an average of 76% EBWL (p = NS). CONCLUSIONS: Preoperative knowledge, assessed by a test, did not predict success after laparoscopic gastric bypass surgery. Patients who do not, at first, have full knowledge of bariatric surgery should not be discriminated against undergoing surgery if they are eventually properly educated.

Laparoscopic repair of a staple-line disruption after an open uncut Roux-en-Y gastric bypass.

The technique of gastric bypass has undergone an evolution over the last 20 years, although it is often individualized based on surgeon preference. Whereas many surgeons divide and separate the gastric pouch from the distal bypassed stomach, some surgeons choose to staple, but not cut and separate the pouch. Staple-line failure resulting in a gastrogastric fistula and weight regain is a worrisome complication. We discuss a case of a patient with an obvious staple-line failure, which resulted in complete weight regain. She underwent laparoscopic repair and was discharged on postoperative day 1. Laparoscopic repair of a staple-line disruption after an open uncut gastric bypass is feasible.

Support group meeting attendance is associated with better weight loss.

BACKGROUND: Support group meetings (SGM) are assumed to be an integral part of success after bariatric surgery. This investigation studies the effect of SGM on weight loss as well as factors associated with attendance of SGM. It is our hypothesis that patients who attend SGM (ASGM) lose more weight than those patients who do not attend SGM (NASGM). METHODS: Postoperative bariatric patients completed a questionnaire regarding their opinions of SGM. Change in body mass index (BMI) was computed for each patient. The patients were then divided into two groups: ASGM and NASGM for data comparison. RESULTS: There were 46 patients in the investigation. Patients in the NASGM group tended to feel that SGM are not needed after bariatric surgery compared to the ASGM group (5.29 vs. 7.06; p = 0.07). Patients in the NASGM group tended to feel that they would lose the same amount of weight with or without attending SGM compared to the ASGM group (5.67 vs. 7.38; p = 0.07). There were no differences in distance to clinic nor in time to clinic between both groups. Gastric bypass patients in the ASGM group had a statistically significantly higher percent decrease in BMI than the patients in the NASGM group (42% vs. 32%; p < 0.03). CONCLUSION: Patients in the ASGM group lose more weight than patients in the NASGM group. The importance of attending SGM should be incorporated in preoperative patient counseling and encouraged during postoperative follow-up visits.

Anti-Xa levels in bariatric surgery patients receiving prophylactic enoxaparin.

BACKGROUND: Limited data exist regarding efficacy and dosing of low-molecular-weight heparins, including enoxaparin, for morbidly obese patients. Prophylactic doses of 30 to 60 mg every 12 h have been described in bariatric surgery patients with appropriate anti-Xa levels reported between 0.18 and 0.6 units/mL. METHODS: Fifty-two laparoscopic gastric bypass or banding patients were enrolled. Patients were divided into two groups by the dose of enoxaparin that was given: Group 1--enoxaparin 30 mg every 12 hours--and Group 2--enoxaparin 40 mg every 12 h. Anti-Xa levels were obtained 4 h after the first and third doses. Levels between 0.18-0.44 units/mL were considered appropriate. RESULTS: There were 19 patients (74% female, mean body mass index [BMI] 48.4 kg/m2) in Group 1 and 33 patients (82% female, mean BMI 48.5 kg/m2) in Group 2. In Group 1, anti-Xa levels were 0.06 and 0.08 units/mL after the first and third doses, respectively. In Group 2, anti-Xa levels were 0.14 and 0.15 units/mL after first and third doses, respectively (p = NS). There was a statistically significant difference in anti-Xa levels between Group 1 first dose and Group 2 first dose (p < 0.05) and between Group 1 third dose and Group 2 third dose (p < 0.05). Percentage of appropriate anti-Xa levels at first dose differed 0% vs. 30.8% (Group 1 vs. Group 2; p = 0.01) and at third dose 9.1% vs. 41.7% (Group 1 vs. Group 2; p = 0.155). CONCLUSION: When prophylactic dose enoxaparin of 30 mg every 12 h was changed to 40 mg every 12 h in bariatric surgery patients, anti-Xa levels significantly increased with prophylactic dose enoxaparin in bariatric surgery patients. The percentage of appropriate levels also increased; however, more than half of the patients receiving 40 mg every 12 hours failed to reach therapeutic levels. No levels were supratherapeutic. Dosage of 40 mg every 12 h may not be sufficient for bariatric surgery patients.

Gastric bypass surgery in rats produces weight loss modeling after human gastric bypass.

BACKGROUND: The study of the mechanisms of weight loss after bariatric surgery requires an animal model that mimics the human procedure and subsequent weight loss. A rat model eliminates the cognitive efforts associated with human weight loss and gain. METHODS: A technique for gastric bypass (Roux-en-Y gastric bypass [RYGB]) was developed in Sprague-Dawley rats. A 1- to 2-cc pouch is created from the uppermost stomach using a linear stapler. A 10-cm biliopancreatic limb and 15-cm Roux limb are anastomosed side to side with running nonabsorbable suture. The gastrojejunostomy is created with a single layer of running nonabsorbable suture. Four rats underwent RYGB. Weight loss was compared to four sham rats that had a midline incision and left 60 min with an open abdomen before closure. RESULTS: RYGB rats lost an average of 16.5% body weight (BW) at 1 week, 22% BW at 2 weeks, 20% BW at 3 weeks, and 11% BW at 4 weeks. The RYGB rat's weight was basically level after 4 weeks. The shams lost an average of 4% BW at 1 week, 1% BW at 2 weeks, and 0% BW at 3 weeks and gained an average of 2% at weeks. Subjectively, the RYGB rats were less interested in chow and frequently had chow left in their cage. CONCLUSION: A Sprague-Dawley rat model for gastric bypass has been developed and yields approximately 11% BW loss. This will allow investigators to objectively view factors associated with weight loss without the confounding cognitive factors in humans.